Tomatoes are widely produced and consumed due to their nutritional content and versatility. However, the tomato is a soft fruit liable to damage and flavour deterioration. Hence, the main challenge for the tomato producing industry is to prevent the high loss incurred during harvest, handling and transportation of the crops. The objective of this study was to investigate the overall nutritional implication of controlled storage of tomatoes using ozone on the ripening process and the basic nutritional components of tomatoes. This investigation was also designed to focus on the effect of different ozone doses on the basic components and properties (carotenoids, ascorbic acid, total antioxidant activity and soluble sugars content) of the quality and dynamic maturity of tomatoes. Green tomatoes (Rio Grande) were treated in glass chambers with ozone enriched air [(air + 2, 7 and 21 mg O3/g tomato) and control (air only)] under humidity and temperature of 90-95% and 14-17 oC respectively. Tomatoes were sampled after 14 days of ozone treatment in the storage chamber and analyzed for different quality parameters (appearance, weight loss, Total Soluble Solids (TSS), titratable acidity, total ascorbic acid and carotene) of the ripening. The variety Elegance tomatoes were selected and the fruits were graded by colour and subjected to treatment with ozone (in doses 0 (clean air), 0.25, 0.50, and1.00 mg O3/g tomatoes) during storage for 6 days under the same humidity and temperature conditions. The fruits were analysed for carotenoids, ascorbic acid content, total antioxidant activity and soluble sugars. Analysis of the fruits clearly showed that ozone significantly delayed the development of colour on the surface, particularly in the low doses, and caused black spots on the surface of the tomatoes, particularly in higher ozone doses. Ozone did not affect the ascorbic acid and titratable acidity content. However ozone did reduce the Total Soluble Solids (TSS) by about 10% at the lowest ozone dose. A high inhibition of accumulation of carotenoids, particularly at low dose, of the tomatoes (Rio Grande) was also observed. Tomatoes (Elegance) under ozone treatments contained higher ß-carotene than those under the control treatment and lycopene content increased during storage in the red stage of tomato fruits. Ascorbic acid (AsA), dehydroascorbic acid (DHA) and the total of AsA and DHA concentrations, and ratios of redox (ASA/ (ASA + DHA) and DHA/AsA in pericarp and pulp of tomatoes tissue, did not show clear differences between the different treatments. The concentrations of the glucose and fructose increased in the tomatoes which were subjected to ozone treatments. Results from this study show that controlled atmosphere storage of tomatoes using ozone is a viable technique which warrants further study.

A vinhaça é o principal subproduto na fabricação do álcool e o que possui maior quantidade de nutrientes em sua composição. Seu poder poluente, cerca de cem vezes maior que esgoto doméstico, é decorrente da sua riqueza em matéria orgânica, baixo pH, corrosividade, elevadas DBO e DQO, além de cor escura e cheiro característico. A aceitação crescente no uso de fungos basidiomicetos em processos de tratamento e/ou biorremediação se deve por apresentarem um sistema enzimático extracelular capaz de romper uma grande quantidade de ligações químicas. Espécies do gênero Pleurotus sp. são conhecidas pela produção de enzimas lignolíticas como manganês-peroxidase, peroxidases e lacases. Também são reportados como alimentos por possuírem como seus maiores constituintes carboidratos e proteínas, seguidos de minerais e baixos teores de gorduras. O presente estudo teve por objetivo avaliar a atividade enzimática de quatro fungos basidiomicetos cultivados em meio de vinhaça líquido e sólido, bem como avaliar as propriedades nutricionais dos micélios como fonte de alimento para peixes da espécie D. rerio. Os fungos Pleurotus sajor-caju CCB 020, Pleurotus sp. CCB 068, P. flabellatus CCB 396 e Pleurotus shimeji, foram cultivados em meio sólido e líquido de vinhaça para análise de atividade enzimática e para crescimento micelial durante 15 dias. A atividade enzimática foi determinada de acordo com protocolo de Szklars et al. (1989) e Kuwahara et al. (1984) a cada 3 dias. Os fungos foram liofilizados e oferecidos aos peixes na proporção de 2% do peso corpóreo dos mesmos e nas quantidades de 50% fungo + 50% ração e 100% fungo em cinco réplicas comparando com um grupo controle tratado com 100% ração por um período de 28 dias. As quatro espécies de Pleurotus apresentaram crescimento satisfatório em meio contendo 100% de vinhaça após 15 dias, sendo obtidos maiores valores com Pleurotus sp. CCB 068 (16,27g). Além disso, observou-se o clareamento e diminuição de turbidez da vinhaça pelos fungos P. sajor-caju CCB 020 e P. shimeji. Em relação à atividade enzimática, os maiores valores para lacase foram obtidos em meio de vinhaça + ágar pelo fungo P. sajor-caju (1.247, 43 UI g-1MS -12º dia) e para peroxidase apresentou, ao 6º dia, atividade de 676,02 UI g-1MS. O mesmo fungo obteve maior valor de MnP no 15º dia de cultivo (318,94 UI L-1) em meio de vinhaça líquido. As análises bromatológicas apresentaram valores nutritivos satisfatórios para os fungos quando comparados à ração comercial, apresentando menores valores somente para proteínas. O teste de alimentação com D. rerio durante 28 dia mostrou que houve perda de biomassa, não significativa estatisticamente e, os valores de sobrevivência dos peixes foram de 100% em todos os tratamentos, indicando que os fungos testados cultivados em vinhaça não apresentaram toxidade. Foi concluído que o uso de fungos do gênero Pleurotus sp. cultivados em vinhaça, além de reduzir compostos tóxicos deste subproduto, é eficiente na produção de enzimas de interesse industrial e seus micélios podem ser inclusos na dieta de animais como suplementos nutricionais. / The vinasse is the principal subproduct in the manufacture of alcohol and the one who has the high amount of nutrients in your composition. Its pollutant power, about a hundred times higher than domestic waste, is due to its richness in organic matter, low pH, corrosivity, high BOD and QOD, in adittion to dark color and characteristic odor. The growing acceptance in the use of basiomycetes fungi in the treatment process and/or bioremediation must be present for an extracellular enzymatic system capable of breaking a large number of chemistry bonds. Species of the gender Pleurotus sp. are known for the lignolytic enzyme production like manganese peroxidase, peroxidases and laccases. Are also reported as food because they have as your major constituint carbohydrates and proteins, follow by minerals and low levels of fat. This study aimed to evaluate the enzymatic activity of four basidiomycetes fungi grown in liquid and solid vinasse medium, and to evaluate the nutricional properties of micelium as a food source for fishes D. rerio. The fungi Pleurotus sajor-caju CCB 020, Pleurotus sp. CCB 068, Pleurotus flabellatus CCB 396 and Pleurotus shimeji were grown in solid and liquid vinasse médium for enzymatic activity assay and for micelial grow during 15 days. The enzyme activity was determined according to protocol Szklars et al. (1989) and Kuwahara et al (1984) every 3 days. The fungi were liophilized and offered tho fishes at 2% of body weight and in amounts of 50% of fungus + 50% ration and 100% of fungus in five repetitions compared with a control group treated with 100% ration for 28 days. The four species of Pleurotus shown satisfactory growth in vinasse médium after 15 days, with highest values with Pleurotus sp. CCB 068 (16,27 g). Besides, was observed the bleaching and tubidity reduction by P. sajor-caju CCB 020 and P. shimeji fungi. Regarding the enzymatic activity, the highest values for laccase was obtained by P. sajor-caju (1.247,43 UI g -1 DM - 12th day) and peroxidase presented, at the 6th day, the activity of 676,02 UI g-1DM. The same fungus had the highest value for MnP on the 15th day of cultivation (318,94 UI L-1) in liquid vinasse médium. The bromatological analysis showed satisfactory nutritional values for the fungi when compared to commercial ration, with lowers values only for proteins. The feeding test with D. rerio during 29 days showed that was biomass loss, but not statisticaly significant, and the survival values of fish were 100% in all treatments, indicating that the tested fungi grown in vinasse showed no toxicity. It was concluded that the use of Pleurotus sp. fungi grown in vinasse, besides the reduction of toxic compounds of this subproduct, is effective in the production of industrial interest enzymes and their micelium can be included in the diet of animals as nutritional suplements.

O estudo da digestibilidade e do aproveitamento biológico do feijão (Phaseolus vulgaris, L. ),variedade Carioca e de suas principais frações protéicas foi realizado em ensaios biológicos com ratos, após tratamento térmico adequado (cocção). À metodologia convencional, baseada no \"Ganho de Peso\" e na razão entre o N ingerido e excretado, seguiu-se uma técnica utilizando feijões e suas frações protéicas previamente marcadas com 15N e 35S. A ingestão das rações causou respostas diferentes nos animais, específicos para cada fonte protéica. Os animais alimentados com o feijão integral tiveram reduzido aproveitamento biológico e excretaram 34% do nitrogênio ingerido, sendo este valor 3-4 vezes superior ao causado pela ingestão da ração controle de caseína. As frações, albumínicas e glutelínicas, apresentaram valores de \"NPR\" e \"Ganhos de Peso\" superiores, apesar de sua relativa baixa digestibilidade (70-80%). A globulina G1, altamente digerível (92%) teve uma utilização biológica muito reduzida, não permitindo o crescimento dos animais. O ensaio biológico do feijão e de suas proteínas, marcados isotopicamente, permitiu diferenciar a origem do nitrogênio e do enxofre fecal, se endógena ou exógena. A concentração de 15N em excesso, determinado nas fazes 12 horas após o início da ingestão das rações marcadas, consideramos ser de origem exógena, sendo esses valores interpretados comparativamente. A ingestão de feijões cozidos causou nos animais uma excreção de nitrogênio proveniente do próprio feijão, 10 vezes superior à elevada perda de nitrogênio endógeno, totalizando o equivalente a 34% do nitrogênio ingerido. Ratos alimentados com a globulina G1 excretaram nas primeiras 12 horas apenas quantidades muito reduzidas de 15N, e mesmo na fase de equilíbrio (4º - 6º dia de ingestão da reação marcada ) quando o 15N excretado corresponde ao exógeno + endógeno já marcado, a perda de N total não ultrapassou 10% do ingerido. A ingestão da fração albumínica, por sua vez, causou uma eliminação de 20% do N total ingerido, com participação tanto do N exógeno como endógeno. A interpretação dos resultados baseados na eliminação do enxofre e de seu radioisótopo 35S, mostrou um perfil de excreção semelhante ao observado para o 15N, embora em níveis levemente superiores. / Studies with growing rats were carried out to determine the digestibility, and nutritive value of beans (Phaseolus vulgaris, L.) Carioca variety, and their major protein fractions, after proper heat treatment in order to inactivate the antiphysiological factors. The conventional method based on weight gain and the relation between the ingested and excreted nitrogen was followed by a balance technique, employing either whole beans or their protein fractions, previously labeled with 15N and 35S. The ingestion of the diets showed different nutritive responses, which were specific for each of the diets. Low biological value and digestibility were observed by rats fed on whole bean-containing diets, and as a consequence an excretion of 34% the ingested nitrogen was noted. This value was 3-4 times higher than the one excreted by the casein-control animals. Higher vakues of \"weight gain\" and NPR were obtained with the albumin and glutelin based diets, although their digestibilities were relatively low (70 - 80%). The globulin G1 was highly digestible (92%) nevertheless it appeared to have very low nutritional values and did not allow the growth of rats. The biological assay with isotopically labeled beans and proteins, allowed to differenciate the origin of fecal nitrogen and sulfur, as exogenous or endogenous. The concentration of 15 N in excess, which appeared in the feces 12 hours after the first ingestion of the labeled diets, was considered to be of exogenous origin; these values can be interpreted comparatively. The ingestion of the cooked whole beans promoted an excretion of exogenous nitrogen, 10 times higher than that excreted by the rats on the globulin G1 diet, which with the high excretion of endogenous nitrogen, totalized 34% of the ingested one. Rats fed on the globulin G1 excreted, in the first 12 hours, only small amounts of 15N, even in the steady - state (4º - 6ºth day on feeding the labeled diet), when the excreted 15N corresponded to both, exogenous and labeled endogenous excretion reached, the maximum loss (about 10% of the ingested total nitrogen). The feeding of albumin based diets stimulated an excretion of 20% of the ingested nitrogen, due to exogenous and endogenous origin. The interpretation of the results based on the balance of total sulfur and their radioactive isotope (35S) showed an excretion pattern, similar to that of the 15N, although in absolute values (of excretion) it was a little higher than that representing the nitrogen loss.

A vinhaça é o principal subproduto na fabricação do álcool e o que possui maior quantidade de nutrientes em sua composição. Seu poder poluente, cerca de cem vezes maior que esgoto doméstico, é decorrente da sua riqueza em matéria orgânica, baixo pH, corrosividade, elevadas DBO e DQO, além de cor escura e cheiro característico. A aceitação crescente no uso de fungos basidiomicetos em processos de tratamento e/ou biorremediação se deve por apresentarem um sistema enzimático extracelular capaz de romper uma grande quantidade de ligações químicas. Espécies do gênero Pleurotus sp. são conhecidas pela produção de enzimas lignolíticas como manganês-peroxidase, peroxidases e lacases. Também são reportados como alimentos por possuírem como seus maiores constituintes carboidratos e proteínas, seguidos de minerais e baixos teores de gorduras. O presente estudo teve por objetivo avaliar a atividade enzimática de quatro fungos basidiomicetos cultivados em meio de vinhaça líquido e sólido, bem como avaliar as propriedades nutricionais dos micélios como fonte de alimento para peixes da espécie D. rerio. Os fungos Pleurotus sajor-caju CCB 020, Pleurotus sp. CCB 068, P. flabellatus CCB 396 e Pleurotus shimeji, foram cultivados em meio sólido e líquido de vinhaça para análise de atividade enzimática e para crescimento micelial durante 15 dias. A atividade enzimática foi determinada de acordo com protocolo de Szklars et al. (1989) e Kuwahara et al. (1984) a cada 3 dias. Os fungos foram liofilizados e oferecidos aos peixes na proporção de 2% do peso corpóreo dos mesmos e nas quantidades de 50% fungo + 50% ração e 100% fungo em cinco réplicas comparando com um grupo controle tratado com 100% ração por um período de 28 dias. As quatro espécies de Pleurotus apresentaram crescimento satisfatório em meio contendo 100% de vinhaça após 15 dias, sendo obtidos maiores valores com Pleurotus sp. CCB 068 (16,27g). Além disso, observou-se o clareamento e diminuição de turbidez da vinhaça pelos fungos P. sajor-caju CCB 020 e P. shimeji. Em relação à atividade enzimática, os maiores valores para lacase foram obtidos em meio de vinhaça + ágar pelo fungo P. sajor-caju (1.247, 43 UI g-1MS -12º dia) e para peroxidase apresentou, ao 6º dia, atividade de 676,02 UI g-1MS. O mesmo fungo obteve maior valor de MnP no 15º dia de cultivo (318,94 UI L-1) em meio de vinhaça líquido. As análises bromatológicas apresentaram valores nutritivos satisfatórios para os fungos quando comparados à ração comercial, apresentando menores valores somente para proteínas. O teste de alimentação com D. rerio durante 28 dia mostrou que houve perda de biomassa, não significativa estatisticamente e, os valores de sobrevivência dos peixes foram de 100% em todos os tratamentos, indicando que os fungos testados cultivados em vinhaça não apresentaram toxidade. Foi concluído que o uso de fungos do gênero Pleurotus sp. cultivados em vinhaça, além de reduzir compostos tóxicos deste subproduto, é eficiente na produção de enzimas de interesse industrial e seus micélios podem ser inclusos na dieta de animais como suplementos nutricionais. / The vinasse is the principal subproduct in the manufacture of alcohol and the one who has the high amount of nutrients in your composition. Its pollutant power, about a hundred times higher than domestic waste, is due to its richness in organic matter, low pH, corrosivity, high BOD and QOD, in adittion to dark color and characteristic odor. The growing acceptance in the use of basiomycetes fungi in the treatment process and/or bioremediation must be present for an extracellular enzymatic system capable of breaking a large number of chemistry bonds. Species of the gender Pleurotus sp. are known for the lignolytic enzyme production like manganese peroxidase, peroxidases and laccases. Are also reported as food because they have as your major constituint carbohydrates and proteins, follow by minerals and low levels of fat. This study aimed to evaluate the enzymatic activity of four basidiomycetes fungi grown in liquid and solid vinasse medium, and to evaluate the nutricional properties of micelium as a food source for fishes D. rerio. The fungi Pleurotus sajor-caju CCB 020, Pleurotus sp. CCB 068, Pleurotus flabellatus CCB 396 and Pleurotus shimeji were grown in solid and liquid vinasse médium for enzymatic activity assay and for micelial grow during 15 days. The enzyme activity was determined according to protocol Szklars et al. (1989) and Kuwahara et al (1984) every 3 days. The fungi were liophilized and offered tho fishes at 2% of body weight and in amounts of 50% of fungus + 50% ration and 100% of fungus in five repetitions compared with a control group treated with 100% ration for 28 days. The four species of Pleurotus shown satisfactory growth in vinasse médium after 15 days, with highest values with Pleurotus sp. CCB 068 (16,27 g). Besides, was observed the bleaching and tubidity reduction by P. sajor-caju CCB 020 and P. shimeji fungi. Regarding the enzymatic activity, the highest values for laccase was obtained by P. sajor-caju (1.247,43 UI g -1 DM - 12th day) and peroxidase presented, at the 6th day, the activity of 676,02 UI g-1DM. The same fungus had the highest value for MnP on the 15th day of cultivation (318,94 UI L-1) in liquid vinasse médium. The bromatological analysis showed satisfactory nutritional values for the fungi when compared to commercial ration, with lowers values only for proteins. The feeding test with D. rerio during 29 days showed that was biomass loss, but not statisticaly significant, and the survival values of fish were 100% in all treatments, indicating that the tested fungi grown in vinasse showed no toxicity. It was concluded that the use of Pleurotus sp. fungi grown in vinasse, besides the reduction of toxic compounds of this subproduct, is effective in the production of industrial interest enzymes and their micelium can be included in the diet of animals as nutritional suplements.

Orientador: Florencia Cecilia Menegalli / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-10T12:33:47Z (GMT). No. of bitstreams: 1 Eik_NenisMaria_M.pdf: 6779419 bytes, checksum: 101dc4e969d705e3431aff6504dc1ef9 (MD5) Previous issue date: 2008 / Resumo: A maioria dos vegetais apresenta alta perecibilidade devido ao elevado conteúdo de água, o que dificulta o comércio, tanto pela distância dos mercados quanto pela sazonalidade, demandando armazenamento e transporte frigorificado de alto custo. O processamento é uma alternativa para aumentar o tempo de prateleira e a disponibilidade durante todo o ano, podendo reduzir as perdas pela impossibilidade de comercialização na forma de fruta fresca. O objetivo geral deste estudo foi avaliar a influência de pré-tratamentos e aplicação de coberturas comestíveis sobre a cinética de secagem e seus efeitos sobre a qualidade física e nutricional de frutas desidratadas. Na primeira etapa deste trabalho, caquis em fatias pré-tratados de diversas maneiras (branqueados com uma solução de ácido cítrico (0,2%, em massa) e ácido ascórbico (0,1%, em massa), branqueados com vapor de água, revestidos com coberturas de farinha de amaranto (4%, em massa) e com cobertura de pectina (2%, em massa)); foram desidratados em secador por convecção de ar aquecido. Em um segundo grupo de ensaios, figos foram pré-tratados (branqueados com uma solução de ácido cítrico (0,2%, em massa) e ácido ascórbico (0,1%, em massa), revestidos com coberturas de farinha de amaranto (4%, em massa) e com cobertura de pectina (2%, em massa)); foram desidratados em secador por convecção de ar aquecido. Foram estabelecidos os parâmetros de concentração, temperatura e tempo de preparação e de aplicação das coberturas, assim como os parâmetros dos processos de branqueamento. A cinética de secagem, em função da velocidade do ar e da temperatura, foi determinada ao longo da secagem. A eficiência da secagem foi medida em função das taxas obtidas com os diferentes pré-tratamentos e condições de secagem. O encolhimento das fatias foi determinado através de medidas de densidade e espessura. A densidade de amostras retiradas ao longo da secagem foi analisada. Para avaliação do efeito dos pré-tratamentos na qualidade do produto, foram realizadas análises de polifenóis, de carotenóides totais e de cor dos produtos fresco e seco. O caqui seco foi avaliado por essas características durante o período de quatro meses de armazenamento / Abstract: Most vegetables and fruits are highly perishable due to a high water conten, which makes it difficult to trade, since seasonality and distance between markets demand costly refrigerated storage and transportation. Increasing shelf life and availability throughout the year by processing reduces losses by marketing of fresh foods. This research aimed at evaluating the influence of pre-treatment and application of edible coatings on the kinetics of drying and their effects on the physical and nutritional quality of dehydrated fruits. In the first stage of this study, persimmon fruit was used in slices, that were pre-treated in various ways, i.e. bleaching with a solution of citric acid (0.2% w/w) and ascorbic acid (0.1 % w/w), bleaching with steam, coating with amaranth flour (4% w/w) and coating with pectin (2% w/w). After each pre-treatment the slices were dehydrated using a convective heated air dryer. In a second series of tests, figs were pre-treated by bleaching with a solution of citric acid (0.2% w/w) and ascorbic acid (0.1 % w/w), coating with amaranth flour (4% w/w) and coating with pectin (2% w/w) and dehydrating in a convective heated air dryer. Concentration, temperature and bleaching parameters were chosen, as well as the time of preparation and application of the coating. The drying kinetics were determined as a function of air velocity and temperature. The drying efficiency was determined by the drying rates obtained with the different pretreatments and conditions. The shrinkage of the slices was determined by measuring density and thickness of samples collected during the drying process. For evaluation of the quality of the fresh product and the dry product, analyses of polyphenols, total carotenoids and color were carried out. Dried persimmon fruit was equally evaluated for its quality during four months of storage / Mestrado / Mestre em Engenharia de Alimentos

Orientador: Florência Cecília Menegalli / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-16T13:52:13Z (GMT). No. of bitstreams: 1 Goncalves_JulianadeAlmeida_M.pdf: 23795201 bytes, checksum: bfbabbd676cb98b26b07e555c628e1a8 (MD5) Previous issue date: 2010 / Resumo: A carambola e fonte de importantes nutrientes como vitaminas, minerais e muitos fitoquimicos que exercem papeis importantes na saude humana. No entanto, o seu elevado conteudo de agua e a interferencia de agentes externos, como oxigenio e microorganismos, tornam esse produto perecivel e de facil deterioracao. O objetivo deste trabalho foi estudar o efeito da formulacao de coberturas comestiveis aditivadas com antioxidantes, aplicadas previamente a secagem, que assegurem a manutencao das propriedades funcionais de carambola em fatias. Na primeira etapa deste trabalho, fatias de carambolas foram revestidas com coberturas de pectina (2% m/m) e acidos citrico (0,5% m/m) e ascorbico (0,5% m/m), com coberturas de alginato (1% m/m) e acidos citrico (0,5% m/m) e ascorbico (0,5% m/m), com coberturas de pectina (2% m/m) e suco de uva (26% m/m) e com coberturas de alginato (1% m/m) e suco de uva (26% m/m), e desidratadas em secador de ar convectivo nas temperaturas de 50, 60 e 70°C, a fim de verificar a influencia da aplicacao das coberturas sobre a cinetica de secagem e sobre o encolhimento das amostras. Na segunda etapa do trabalho, as amostras foram novamente revestidas, secas e entao armazenadas por 21 dias, com temperatura controlada de 35°C, para avaliar suas caracteristicas nutricionais e fisicas. Verificou-se que a aplicacao das coberturas nao influenciou na cinetica de secagem. A manutencao da forca maxima de ruptura foi mais eficaz nas amostras revestidas, e a retencao da cor foi mais eficiente nas amostras cobertas com pectina e acidos. Em relacao as propriedades nutricionais, a aplicacao das coberturas de pectina auxiliou na retencao de carotenoides, vitamina C e polifenois / Abstract: The star fruit is a source of important nutrients such as vitamins, minerals and phytochemicals that play many important roles in human health. However, its high water content and the interference of external agents, such as oxygen and microorganisms, make this perishable product and easy to damage. The aim of this work was to study the effect of the formulation of biodegradable coatings added with antioxidants, applied prior to drying to ensure the maintenance of functional properties of star fruit slices. In the first stage of this work, star fruit slices were coated with pectin (2% w / w) and citric acid (0.5% w/w) and ascorbic (0.5% w / w) with coat of alginate (1% w / w) and citric acid (0.5% w / w) and ascorbic (0.5% w/ w) with coat of pectin (2% w / w) and grape juice (26%, w / w) and coated with alginate (1% w / w) and grape juice (26% w / w) and were dried in an air convective dryer at temperatures of 50, 60 and 70 ° C to verify the influence the application of the coating on the kinetics of drying and the shrinkage of the samples. In the second stage of this work, the samples were again coated, dried and then stored for 21 days, at temperatures of 35°C, to evaluate their nutritional and physical characteristics. It was found that the application of the coating did not influence the drying kinetics. The maintaining of the maximum tensile was more effective in samples coated and the color retention was more efficient in samples coated with pectin and acid. In relation to nutritional properties, the application of the coatings of pectin help in the retention of carotenoids, vitamin C and polyphenols / Mestrado / Mestre em Engenharia de Alimentos

Marama bean (Tylosema esculentum (Burch) A. Schreib) is an underutilised, drought-tolerant legume native to the drier parts of Botswana, Namibia and South Africa. The bean is comparable to soya beans in protein content and quality whereas its oil content is comparable to that of peanuts. By adding value to the marama bean through processing into protein-rich flours, its utilisation may be increased. Therefore, one of the objectives of this study was to adopt suitable low-cost processing technologies used for soya processing to produce protein-rich marama bean flours. The effect of dry heating of whole marama beans on lipoxygenase enzymes of its defatted flour was determined since oxidative rancidity catalysed mainly by lipoxygenase enzymes can reduce the shelf-life of the flour. The presence of trypsin inhibitors can affect the protein digestibility of the marama bean flour adversely. The effect of dry heating of whole marama beans on in-vitro protein digestibility and amino acid content of its defatted flour was determined. Lastly, the effect of dry heating of whole marama beans on the protein-related functional properties of the resultant defatted flour was determined. The presence of lipoxygenase iso-enzymes (L-1 and L-2) activity in marama beans was determined by a visual and spectrophotometeric method using unheated soya beans as reference. Lipoxygenase iso-enzymes (L-1 and L-2) activity was not detected in marama beans. This may possibly suggest that these lipoxygenase iso-enzymes are absent or possibly inhibited in marama beans. In an attempt to optimise dry heating to inactivate trypsin inhibitors in marama beans, whole marama beans were dry heated at 100°C, 120°C and 150°C, respectively for 20 min. Defatted flours prepared from the heated marama beans (HMF’s) were analysed for their trypsin inhibitor activity using defatted flours from unheated marama beans (UMF) and soya beans (USF) as control and reference samples, respectively. Trypsin inhibitor activity in UMF was almost four and half times higher than in USF. Dry heating of whole marama beans at 150°C/20 min significantly reduced the trypsin inhibitor activity in its defatted flour to almost zero probably due to inactivation of the trypsin inhibitor. The effect of dry heating of whole marama beans at 150°C/20 min on the physico-chemical, nutritional and protein-related functional properties of defatted marama bean flour was determined. UMF was used as a control while USF and HSF were used as reference samples. HMF had higher protein content but lower fat content than UMF. It is suggested that dry heating disrupted the lipid bodies of the marama beans allowing more oil to be expelled during coarse milling of the flour. Heating significantly reduced the L* values of marama and soya bean flours possibly due to Maillard browning reactions. Heating significantly increased in-vitro protein digestibility of marama and soya bean flours probably due to protein denaturation and inactivation of trypsin inhibitors. Heating generally decreased the amino acid contents of marama and soya bean flours possibly due to chemical modification of the amino acids. UMF and HMF can potentially be used to improve protein quality in marama-cereal composite flours, porridges and breads. Heating significantly decreased the nitrogen solubility index (NSI) and emulsifying capacity (EC) of marama and soya bean flours possibly due to protein denaturation and/or cross-linking. This may make HMF and HSF not suitable for applications in emulsion type meat products such as sausages because emulsion formation is critical during processing of sausages. Heating significantly decreased the foaming capacity of soya flour but did not have an effect on that of marama bean flour probably due to their high residual fat content which may have disrupted protein films during foam formation. UMF has a potential to be used in comminuted meat products because of its relatively high NSI, EC and OAC. The laboratory process used in this study can be modified and adopted by SME’s to produce defatted marama bean flours with potential applications in bakery and meat products and as a protein supplement in composite marama-cereal products. / Dissertation (MSc)--University of Pretoria, 2011. / Food Science / unrestricted

La nutrition constitue l'un des facteurs déterminants du développement ou de la prévention de diverses pathologies. Parmi les trois classes de nutriments majeurs, les lipides alimentaires occupent une place essentielle dans cette relation nutrition-santé puisque leur déséquilibre qualitatif est impliqué dans l'incidence des maladies cardiovasculaires. L'importance de l'équilibre alimentaire justifie le développement de produits fonctionnels au profil nutritionnel amélioré. En parallèle, suite à la prise de conscience de l'impact environnemental de la production alimentaire, il est aujourd'hui important d'inscrire le choix des matières premières et des procédés dans une démarche de développement durable.Dans ce contexte, les travaux menés durant cette thèse concernent tout d'abord l'amélioration des propriétés nutritionnelles d'une matière grasse végétale tartinable par réduction de sa teneur en acides gras (AG) saturés délétères, mais également la limitation de son impact environnemental par réduction des ingrédients issus de la filière palme. La mise au point d'un procédé d'interestérification enzymatique vise à ajuster les propriétés rhéologiques du produit sans modifier le profil global en AG, et sans utiliser de solvants ou produits chimiques grâce à l'action d'un biocatalyseur (lipase). Ces travaux ont conduit au développement jusqu'au stade pilote d'un substitut interestérifié par voie enzymatique permettant de réduire la teneur en AG saturés délétères de 65% et l'utilisation de dérivés d'huile de palme de 70% tout en maintenant une fonctionnalité similaire au produit actuel. En parallèle, un procédé enzymatique à également été exploité dans l'étude d'une nouvelle méthode d'analyse de la régiodistribution : l'évaluation des sélectivités de la lipase de Rhizopus oryzae a montré son potentiel pour l'analyse de la position sn-2 des triacylglycérols contenant des AG à chaines moyennes. / Nutrition is one of the main factors contributing to various diseases occurrence or prevention. Among the three major types of nutrients, dietary lipids are essential in this nutrition-health relationship since lipid disorder is associated with an increased risk of cardiovascular diseases. Thus, the importance of a healthy diet explains the development of functional foods with improved nutritional properties. Furthermore, with environmental impact of food production being a growing concern for consumers, selection of raw materials and processes should meet the requirements for sustainable development. In this context, this work concerns the improvement of the nutritional properties of a vegetable oil spread by reducing its unhealthy fatty acids (FA) content, but also the limitation of its environmental impact by minimizing the use of palm oil products. An enzymatic interesterification process has been developed to adapt rheological properties without modifying FA profile nor using solvents and chemical products by action of a biocatalyst (lipase). This work led to the pilot-scale development of an enzymatically interesterified substitute allowing to reduce the unhealthy FA content by 65%, and the use of palm oil products by 70% while keeping a functionality similar to the current product.At the same time, an enzymatic approach has also been used in the investigation of a new method for regiodistribution analysis. Thus, Rhizopus oryzae lipase appeared to be a good candidate for the sn-2 position analysis of triacylglycerols containing medium chain fatty acids.

O estudo da digestibilidade e do aproveitamento biológico do feijão (Phaseolus vulgaris, L. ),variedade Carioca e de suas principais frações protéicas foi realizado em ensaios biológicos com ratos, após tratamento térmico adequado (cocção). À metodologia convencional, baseada no \"Ganho de Peso\" e na razão entre o N ingerido e excretado, seguiu-se uma técnica utilizando feijões e suas frações protéicas previamente marcadas com 15N e 35S. A ingestão das rações causou respostas diferentes nos animais, específicos para cada fonte protéica. Os animais alimentados com o feijão integral tiveram reduzido aproveitamento biológico e excretaram 34% do nitrogênio ingerido, sendo este valor 3-4 vezes superior ao causado pela ingestão da ração controle de caseína. As frações, albumínicas e glutelínicas, apresentaram valores de \"NPR\" e \"Ganhos de Peso\" superiores, apesar de sua relativa baixa digestibilidade (70-80%). A globulina G1, altamente digerível (92%) teve uma utilização biológica muito reduzida, não permitindo o crescimento dos animais. O ensaio biológico do feijão e de suas proteínas, marcados isotopicamente, permitiu diferenciar a origem do nitrogênio e do enxofre fecal, se endógena ou exógena. A concentração de 15N em excesso, determinado nas fazes 12 horas após o início da ingestão das rações marcadas, consideramos ser de origem exógena, sendo esses valores interpretados comparativamente. A ingestão de feijões cozidos causou nos animais uma excreção de nitrogênio proveniente do próprio feijão, 10 vezes superior à elevada perda de nitrogênio endógeno, totalizando o equivalente a 34% do nitrogênio ingerido. Ratos alimentados com a globulina G1 excretaram nas primeiras 12 horas apenas quantidades muito reduzidas de 15N, e mesmo na fase de equilíbrio (4º - 6º dia de ingestão da reação marcada ) quando o 15N excretado corresponde ao exógeno + endógeno já marcado, a perda de N total não ultrapassou 10% do ingerido. A ingestão da fração albumínica, por sua vez, causou uma eliminação de 20% do N total ingerido, com participação tanto do N exógeno como endógeno. A interpretação dos resultados baseados na eliminação do enxofre e de seu radioisótopo 35S, mostrou um perfil de excreção semelhante ao observado para o 15N, embora em níveis levemente superiores. / Studies with growing rats were carried out to determine the digestibility, and nutritive value of beans (Phaseolus vulgaris, L.) Carioca variety, and their major protein fractions, after proper heat treatment in order to inactivate the antiphysiological factors. The conventional method based on weight gain and the relation between the ingested and excreted nitrogen was followed by a balance technique, employing either whole beans or their protein fractions, previously labeled with 15N and 35S. The ingestion of the diets showed different nutritive responses, which were specific for each of the diets. Low biological value and digestibility were observed by rats fed on whole bean-containing diets, and as a consequence an excretion of 34% the ingested nitrogen was noted. This value was 3-4 times higher than the one excreted by the casein-control animals. Higher vakues of \"weight gain\" and NPR were obtained with the albumin and glutelin based diets, although their digestibilities were relatively low (70 - 80%). The globulin G1 was highly digestible (92%) nevertheless it appeared to have very low nutritional values and did not allow the growth of rats. The biological assay with isotopically labeled beans and proteins, allowed to differenciate the origin of fecal nitrogen and sulfur, as exogenous or endogenous. The concentration of 15 N in excess, which appeared in the feces 12 hours after the first ingestion of the labeled diets, was considered to be of exogenous origin; these values can be interpreted comparatively. The ingestion of the cooked whole beans promoted an excretion of exogenous nitrogen, 10 times higher than that excreted by the rats on the globulin G1 diet, which with the high excretion of endogenous nitrogen, totalized 34% of the ingested one. Rats fed on the globulin G1 excreted, in the first 12 hours, only small amounts of 15N, even in the steady - state (4º - 6ºth day on feeding the labeled diet), when the excreted 15N corresponded to both, exogenous and labeled endogenous excretion reached, the maximum loss (about 10% of the ingested total nitrogen). The feeding of albumin based diets stimulated an excretion of 20% of the ingested nitrogen, due to exogenous and endogenous origin. The interpretation of the results based on the balance of total sulfur and their radioactive isotope (35S) showed an excretion pattern, similar to that of the 15N, although in absolute values (of excretion) it was a little higher than that representing the nitrogen loss.

Tomatoes are widely produced and consumed due to their nutritional content and versatility. However, the tomato is a soft fruit liable to damage and flavour deterioration. Hence, the main challenge for the tomato producing industry is to prevent the high loss incurred during harvest, handling and transportation of the crops. The objective of this study was to investigate the overall nutritional implication of controlled storage of tomatoes using ozone on the ripening process and the basic nutritional components of tomatoes. This investigation was also designed to focus on the effect of different ozone doses on the basic components and properties (carotenoids, ascorbic acid, total antioxidant activity and soluble sugars content) of the quality and dynamic maturity of tomatoes. Green tomatoes (Rio Grande) were treated in glass chambers with ozone enriched air [(air + 2, 7 and 21 mg O3/g tomato) and control (air only)] under humidity and temperature of 90-95% and 14-17 oC respectively. Tomatoes were sampled after 14 days of ozone treatment in the storage chamber and analyzed for different quality parameters (appearance, weight loss, Total Soluble Solids (TSS), titratable acidity, total ascorbic acid and carotene) of the ripening. The variety Elegance tomatoes were selected and the fruits were graded by colour and subjected to treatment with ozone (in doses 0 (clean air), 0.25, 0.50, and1.00 mg O3/g tomatoes) during storage for 6 days under the same humidity and temperature conditions. The fruits were analysed for carotenoids, ascorbic acid content, total antioxidant activity and soluble sugars.Analysis of the fruits clearly showed that ozone significantly delayed the development of colour on the surface, particularly in the low doses, and caused black spots on the surface of the tomatoes, particularly in higher ozone doses. Ozone did not affect the ascorbic acid and titratable acidity content. However ozone did reduce the Total Soluble Solids (TSS) by about 10% at the lowest ozone dose. A high inhibition of accumulation of carotenoids, particularly at low dose, of the tomatoes (Rio Grande) was also observed. Tomatoes (Elegance) under ozone treatments contained higher ß-carotene than those under the control treatment and lycopene content increased during storage in the red stage of tomato fruits. Ascorbic acid (AsA), dehydroascorbic acid (DHA) and the total of AsA and DHA concentrations, and ratios of redox (ASA/ (ASA + DHA) and DHA/AsA in pericarp and pulp of tomatoes tissue, did not show clear differences between the different treatments. The concentrations of the glucose and fructose increased in the tomatoes which were subjected to ozone treatments. Results from this study show that controlled atmosphere storage of tomatoes using ozone is a viable technique which warrants further study. / Libyan government